Missing Dependency libreadline7

[myxxmikeyxx]

sudo apt --allow-downgrades install ./wpasupplicant_2.4-1+deb9u6_armhf.deb
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
Note, selecting 'wpasupplicant' instead of './wpasupplicant_2.4-1+deb9u6_armhf.deb'
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 wpasupplicant : Depends: libreadline7 (>= 6.0) but it is not installable
E: Unable to correct problems, you have held broken packages.

This was on the latest raspberry pi image (Bullseye I think). I tried to do sudo apt-get install libreadline7 but it can not find the package. It has options for libreadline5 6 & 8 but not 7.

[Oliver-Johnson]

sudo apt --allow-downgrades install ./wpasupplicant_2.4-1+deb9u6_armhf.deb
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
Note, selecting 'wpasupplicant' instead of './wpasupplicant_2.4-1+deb9u6_armhf.deb'
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 wpasupplicant : Depends: libreadline7 (>= 6.0) but it is not installable
E: Unable to correct problems, you have held broken packages.

This was on the latest raspberry pi image (Bullseye I think). I tried to do sudo apt-get install libreadline7 but it can not find the package. It has options for libreadline5 6 & 8 but not 7.

I get exactly the same problem.

[myxxmikeyxx]

I followed this link to install it.
I think I still ran into other problems but if you do comment them and I will see what I can do to help.

Edit: I have since tried to install an old version (Raspbian Stretch but I might need to go to an older version of stretch that natively has wpasupplicant_2.4-1+deb9u6_armhf.deb installed because the last release is on a newer version).
I know not everyone can use an older release if they are using a raspberry pi 4, but Pi 3 I think can and anything earlier

[ReggaeUlli]

I downloaded the file manually from a mirror listed on this site:
https://packages.debian.org/buster/libreadline7

For example:
wget http://ftp.fr.debian.org/debian/pool/main/r/readline/libreadline7_7.0-3_armhf.deb

And then installed it manually using:
sudo apt-get install ./libreadline7_7.0-3_armhf.deb

after that the downgrade of wpa_supplicant worked fine for me